The purpose of this study is to understand the effects of maternal employment among single mothers on the development of low-income adolescents. The proposed analyses aim to bridge the empirical findings from two areas of research on adolescent development by focusing on several key features of maternal employment and neighborhood context, in particular, economic disadvantage and social organization. More specifically, I intend to address the following questions: What is the effect of entry into and loss of maternal employment and characteristics of employment on the development of low-income adolescents? How does this effect differ during transitions from early to later adolescence versus transitions from late adolescence to early adulthood? Controlling for a variety of family and child level observed and unobserved characteristics, how does neighborhood context influence these effects? There are four key contributions of this study. First, by having data from four large urban areas post 1998 on a representative sample of welfare and working-poor families the findings can be generalized to a broader population of low-income single-parent families than has been possible in prior studies. Second, the data have multiple types of variation that can be exploited in empirical models--longitudinal information at a neighborhood, family as well as child level and cross-sectional neighborhood variation by family as well as child--to control for confounding unobserved or difficult to measure characteristics in estimating these relationships. Third, the large sample of low-income youth provide the power to examine effects separately for subgroups, particularly by age depicting transitions in adolescent development as well as racial/ethnic background and immigrant status (in addition to relative levels of disadvantage of the family, family and sibling structure). Fourth, the neighborhood data include the decennial census data available to most researchers as well as a wealth of annual indicators collected from local administrative agencies including child welfare. This study is a substantive opportunity to understand the economic determinants of adolescent development among low-income single-parent families. The findings will inform both developmental and economic theory as well as policy.